Adjective
Having the form of a bunch of grapes; like a cluster of grapes, as a mineral presenting an aggregation of small spherical or spheroidal prominences.
Source: Webster's dictionaryPrehnite crystallizes in the orthorhombic crystal system, and most oftens forms as stalactitic or botryoidal aggregates, with only just the crests of small crystals showing any faces, which are almost always curved or composite. Source: Internet
Turquoise By Joe Dan Lowry, p.34 Imitations Some natural blue to blue-green materials, such as this botryoidal chrysocolla with drusy quartz, are occasionally confused with, or used to imitate turquoise. Source: Internet